"Deicide" buff on Shard of the Shattered Lance sword damage bonus calculation issue

Playing a cold shatter strike build, and when I have the proc for Deicide my damage does not seem to increase as much as it should.

Shatter Strike without the Deicide Buff is 65,560dps, with the buff it only increases to 65,942dps. So it’s only increasing my dps by 382. A far cry from the 20% (multiplicative) that the ability states.

Player.log (310.8 KB)

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